Mike,
Out of interest,when did the Lancashire Canals open?
It is always difficult to timeline some of the canal building schemes but one thing is for certain, in most if not all cases the driving force in England at least was to get supplies of coal to where it was needed. The canals provided this function and in doing so had the added benefit of reducing the cost coal.
As for who was first, well because canals crossed multiple landowners, an Act of Parliament was needed to initiate the process. So the following timeline can be established:-
1755 Act of Parliament granted for the building of the Sankey Canal.
1757 Sankey Canal opened.
1759 Act of Parliament granted for the building of the Bridgewater Canal.
1761 Bridgewater Canal opened.
The most probable reason why the Bridgewater is accredited as being the first canal is in part due to the fact that the Sankey Canal did in places follow the original line of the Sankey Brook, whereas the Bridgewater did not follow any natural watercourse.. There is of course the promotional side, even in those days the first, the biggest, the best had a sway on those who invested in such ventures. Inevitably it lead to facts being clouded after all, why let the facts get in the way of a good story holds good then just as much as it does today.
Peter.
The Sankey Canal was later known as the St Helens Canal.